Lubricant compositions containing alkylene oxide polymers and sulfur

ABSTRACT

Lubricant compositions are provided containing anti-wear amounts of mixtures of an alkylene oxide polymer and sulfur.

United States Patent [1 1 Davis et al.

l l LUBRICANT COMPOSITIONS CONTAINING ALKYLENE OXIDE POLYMERS AND SULFUR[75] Inventors: Robert H. Davis, Pitmzm; Edward A.

Oberright, Woodbury; John W. Schick, Cherry Hill, all of NJ.

[73] Assignee: Mobil Oil Corporation. New York 5 Nov. 11, 1975 {56]References Cited UNITED STATES PATENTS 3130.159 4/1964 SIedIHUmWm, I.351 31 FOREIGN PATENTS OR APPLICATIONS 45l.372 8/1936 UniIedkingdumumm... 352/.

Prinmry Erumiuer-Delbert E. Gantz .-lssisrunt Emmiucr-J. Vaughn Almrucy.Agent, or FirmCharles A, Huggett; Rurmond W. Barclay; Benjamin I.Kaufman [57] ABSTRACT Lubricant compositions are provided cnnlainingunliwealr amounts of mixtures of an ulkylene oxide pol)- mer and sulfur.

[5 Claims. N0 Drawings LUBRICANT COMPOSITIONS CONTAINING ALKYLENE OXIDEPOLYMERS AND SULFUR BACKGROUND OF THE INVENTION cant compositions, suchas lubricating oils and greases, 0

which normally exhibit wearing effect on machinery with which they maycome into contact and, in some instances, even result in welding action.

2. Description of the Prior Art The prior art has long recognized thatlubricant compositions such as lubricating oils (including mineraloilbased and synthetic oil-based compositions) and greases, exhibit wearand even welding effects on metal parts with which they may come intocontact in performing their function as lubricants. In this respect,alkylene oxide polymers, for example, fatty alcohol polyglycol ethershave been suggested for use as anti-wear agents in lubricatingcompositions, but 'have been found lacking in exhibiting a relativelyhigh degree of anti-wear effect and, in some instances, have alsoexhibited welding effects.

Of particular significance, insofar as the lubricant compositions of thepresent invention are concerned, is the ability to improve the anti-wearproperties of lubricating media which may comprise liquid hydrocarbonoils, in the form of either a mineral oil or a synthetic oil, oremulsions or in the form of a grease in which any of the aforementionedoils are employed as vehicles. In general, mineral oils, employed as thelubricant or grease vehicle, may be of any suitable lubricatingviscosity range as, for example, from about 45 SSU at 100F. to about6,000 SSU at I00F., and preferably, from about 50 SSU at 2l0F. to about250 SSU at 210F. These oils may have viscosity indexes varying frombelow 0 to about I00 or higher. Viscosity indexes from about 70 to about95 are preferred. The average molecular weights of these oils may rangefrom about 250 to 800. Where the lubricant is to be employed in the formof a grease, the lubricating oil is generally employed in an amountsufficient to balance the total grease composition after accounting forthe desired quantity of the thickening agent and other additivecomponents to be included in the grease formulation.

In instances where synthetic oils, or synthetic oils employed as thevehicle for the grease, are desired in preference to mineral oils, or incombination therewith, various compounds of this type may besuccessfully utilized. Typical synthetic vehicles includepolyisobutyiene, polybutenes, hydrogenated polydecenes, polypropyleneglycol, polyethylene glycol, trimethylol propane esters, neopentyl andpentaerythritol esters, di(2-ethyl hexyl) sebacate, di( 2-ethylhexyl)adipate, di(butyl phthalate), fluorocarbons, silicate esters,silanes, esters of phosphorous-containing acids, liquid ureas, ferrocenederivatives, hydrogenated mineral oils, chain-type polyphenyls,siloxanes and silicones (polysiloxanes), alkyl-substituted diphenylethers typified by a butylsubstituted bis (p-phenoxy phenyl) ether,phenoxy phenylethers, etc.

SUMMARY OF THE INVENTION It has now been found that increased anti-wear,and even anti-weld properties can be imparted to lubricant 2compositions by incorporating therein mixtures of alkylene oxidepolymers and sulfur.

In general, the alkylene oxide polymers, which are commerciallyavailable anti-wear agents, can be prepared by the reaction of from 1 to30 moles of an alkylene oxide with from to 99 moles of an alcohol,amine, amide, organic acid, phenol or mercaptan.

The sulfur employed in the novel mixtures of the present invention maycomprise elemental sulfur or a sulfur-containing material or sulfurcompound. The term sulfur is intended to include elemental sulfur aswell as organic sulfur compounds. Insofar as elemental sulfur isconcerned, this is intended to include sulfur powders having any of theallotropic forms and flowers of sulfur. In addition, alkyl sulfides maybe employed including dialkyl and disulfides, unsymmetrical alkylsulfides, disulfides and polysulfides in which the alkyl groups havecarbon atoms ranging from I to 20. There may also be employed aromaticsulfides including phenyl sulfides and substituted-aryl polysulfides.Particularly preferred of the aromatic sulfides is dibenzyl disuIfide.These sulfides may contain up to about l0 atoms of sulfur per mole ofsulfide. Also included in the sulfur compounds, that may be employed inthe synergistic mixtures of the present invention, are those describedin U.S. Pat. No. 2,993,858.

In general, the aforementioned alkylene oxide polymers and sulfur may beemployed in any desired proportion. For most applications, the sulfur inthe mixture can be employed in an amount from about .01 to about l5%,and preferably, in an amount from about 0.05 to about 5%, by weight, ofthe total weight of the mixture. Furthermore, the mixture itself, formost applications, may be employed in the lubricant composition in anamount from about 0.1 to about 30%, and preferably, in an amount fromabout 3 to about 10%, by weight, of the total weight of the lubricantcomposition.

DESCRIPTION OF SPECIFIC EMBODIMENTS In order to demonstrate theimprovement in metalcutting activity realized by employing theabovedescribed novel mixtures in lubricant compositions, compared withthat realized by employing anti-wear components of the above-describedmixtures, individually, comparative data were obtained as shown in theexamples of the following tables.

The data were obtained by means of a Tapping Efficiency Test and, ingeneral, the procedure of this test involves measurement of torquedeveloped in an internal threading operation employing SAE 1020hotrolled steel. In this test, thirty torque values are obtained withthe test fluid and compared with thirty reference fluid values to obtainTapping Efficiency i.e.

Ave. 30 Reference Fluid Torque Values X 100 Ave. 30 Test Fluid TorqueValues 5% Tapping Efficiency drill press equipped with a table which isfree to rotate about the center on ball-bearings. A torque arm isattached to this floating table" and the arm in turn activates a springscale, so that the actual torque during the tapping. with the oil beingevaluated, is measured directly. The same conditions used in evaluatingthe test oil are employed in tapping with a strong oil which hasarbitrarily been assigned an efficiency of 100%. The average torque inthe test oil is compared to that of the standard and a relativeefficiency is calculated on a percentage basis. For example.

Torque with standard reference oil 19.3 Torque with test oil 19.8Relative efficiency of test oil l9.3/l9.8 X 100 97.4

This test is described by C. D. Flemming and L. H. Sudholz inLubrication Engineering. volume 12, No. 3,

May-June I956. pages 199 to 203, and also in US. Pat. 2

4 It should be noted. in accordance with the foregoing TappingEfficiency Test that it" the test fluid torque values exceed thereference value. Tapping Efficiency is below 100%. Criteria for productacceptance are evaluated as follows:

Tapping Efficiency Comments 100; Fluid considered outstanding and shouldoutperform reference product in severe cutting operations. Acceptablerange for moderate duty cutting fluids.

All products with Tapping Efficiencies below 80% are consideredunacceptable. Torque values are erratic. frequently due to tap stickin;and/or breakage.

Employing the foregoing parameters the following data were obtained withcomparisons to sulfur and a variety of allcoxylated materials.

TABLE I Tapping Test Results Emulsifiable, Oil Dispersible EthyleneOxide Polymers Plus Sulfur Z wL-sulfurized Tapping I50 SUS at l00F.Efficiency Z Cl WL-l 50 SUS at Paraffinic Oil SAE I020 Example Additive100F. Paraffinic Oil (0.601 Added S.) H.R. Steel l Reference Fluid A l0080 2 Reference Fluid B I00 87 Ethylene Oxide Amine 3 Ethylene OxideOleylaminc 7 78 4 7 I03 Ethylene Oxide Amide 5 Ethylene OxideOlcylarnide 7 76 6 7 1 l5 Ethylene Oxide Mercaptun 7 Ethylene OxideDodecylmercaptan 7 69 8 7 I09 Ethylene Oxide Acid 9 Ethylene Oxide OleicAcid 7 82 ll) 92 Ethylene Oxide Phenol l l Ethylene Oxide Octylphenol 775 I2 7 99 Ethylene Oxide Alcohols l3 Polyoxyethylene Oleyl Ether 7 8]l4 7 [26 I5 Polyoxyethylcne Cetyl Ether 7 77 I6 7 H3 l7 PolyoxyethyleneLauryl Ether 7 76 '8 7 I l5 l9 Ethoxylatcd Castor Oil 7 92 7 W6 TABLE llTapping Test Results Non Emulsive. Oil Soluble Alkylene Oxide PolymersSulfur k Wt. Sulf. I SUS at l00F. Tapping Elfic. 1' Wt. 150 SUS atParaffinic Oil '1, SAE I020 Example Additive l00F. Paraffinic Oil (0.68%Added S.) H.R. Steel lmides Prepared from Polybutenyl Succinic Anhydride8t Amino Polyoxypropylene Polymers 2! 2M polybutenyl succinic anhydride22 73 (2300 MW) lM diamino polyoxypropylene (2000 MW) 22 1 L54 l03 23 lMpolybutenyl succinic anhydride 7 (1200 MW) IM diamino polyoxypropylene(2000 MW) Complex Esters 24 Prepared via reaction 7 72 AzelaicAcid/Propylene Oxide/ lsooctanol TABLE Il-continued Tapping Test ResultsNon Emulsive, Oil Soluble Alkylenc Oxide Polymers Sulfur Z Wt. Sulf. I50SUS at 100F. Tapping Effic. 71 Wt. 150 SUS at Paruffinic Oil it, SAEI020 Example Additive lOll'F. Paral'finic Oil (0.68% Added 5.) H.R.Steel Azelaic Acid/Propylene Oxide) 7 I08 Isnoctanol From Table I, asshown by Examples 3, 5, 7, etc., it will be noted that all sulfur-freeethoxylated materials would be considered unsatisfactory lubricants whenadded to mineral oil. However, if these materials are combined withsulfur. as shown by Examples 4, 6, 8, etc. tapping efficiencies greatlyexceed values obtained for sulfurized mineral oil. It should also benoted that all compositions described in Table I, Examples 3-20, areemulsifiable, i.e., they can be used in the neat form or combined withwater to form an emulsion which can exhibit lubricating properties. Thisemulsifiable tendency is desirable for many applications. However, theability to combine with water may be undesirable in situations wherecorrosion and/or lube oil reclamation problems are involved. In order,therefore, to minimize this tendency for ethoxylated additives tocombine with water, a number of alkoxylated compounds were synthesizedinvolving imide and ester formations. A summary of the tapping resultsobtained from these nonemulsifiable oil soluble products are shown inTable II. In every instance cutting efficiency was improved when thesecompounds were combined with sulfur.

While this invention has been described with reference to preferredcompositions and components therefor, it will be understood by thoseskilled in the art that departure from the preferred embodiments can beeffectively made and are within the scope of the specification.

We claim:

I. A lubricant composition containing an anti-wear amount of a mixtureof an alkylene oxide polymer and sulfur.

2. A lubricant composition, as defined in claim I, wherein said alkyleneoxide polymer comprises the reaction product of about I to about molesof an alkylene oxide and about 70 to 99 moles ofa member of the groupconsisting of alkanols, fatty acids, and alkylphen- 015.

3. A lubricant composition, as defined in claim 1, wherein saidcomposition comprises a mineral-oil based composition.

4. A lubricant composition. as defined in claim I, wherein saidcomposition comprises a synthetic-oil based composition.

5. A lubricant composition, as defined in claim 1, wherein saidcomposition comprises an oil of lubricating viscosity in the range fromabout 45 SSU at 100F. to about 6000 SSU at 100F.

6. A lubricant composition, as defined in claim 1, wherein saidcomposition comprises an oil of lubricating viscosity in the range fromabout 50 SSU at 210F. to about 250 SSU at 210F.

7. A lubricant composition, as defined in claim 1, wherein saidcomposition comprises a grease.

8. A lubricant composition, as defined in claim I, wherein the sulfur insaid mixture is present in an amount from about 0.0I to about l57c, byweight. of the total weight of the mixture.

9. A lubricant composition, as defined in claim I, wherein the sulfur insaid mixture is present in an amount from about 0.5 to about 5%, byweight, of the total weight of the mixture.

10. A lubricant composition, as defined in claim I, wherein said mixtureis present in an amount from about 0.I to about 30%, by weight, of thetotal weight of the composition.

11. A lubricant composition, as defined in claim I, wherein said mixtureis present in an amount from about 3 to about l07r. by weight, of thetotal weight of the composition.

12. A mixture of an alkylene oxide polymer and sulfur.

13. A mixture, as defined in claim 12, wherein said alkylene oxidepolymer comprises the reaction product of about I to about 30 moles ofan alkylene oxide and about to 99 moles ofa member of the groupconsisting of alkanols, fatty acids, and alkylphenols.

14. A mixture, as defined in claim 12, wherein the sulfur is present inan amount from about 0.0l to about l5%, by weight, of the total weightof the mixture.

15. A mixture, as defined in claim 12, wherein the sulfur is present inan amount from about 0.5 to about 5%, by weight, of the mixture.

i l I

1. A LUBRICANT COMPOSITION CONTAINING AN ANTI-WEAR AMOUNT OF A MIXTUREOF AN ALKYLENE OXIDE POLYMER AND SULFUR.
 2. A lubricant composition, asdefined in claim 1, wherein said alkylene oxide polymer comprises thereaction product of about 1 to about 30 moles of an alkylene oxide andabout 70 to 99 moles of a member of the group consisting of alkanols,fatty acids, and alkylphenols.
 3. A lubricant composition, as defined inclaim 1, wherein said composition comprises a mineral-oil basedcomposition.
 4. A lubricant composition, as defined in claim 1, whereinsaid composition comprises a synthetic-oil based composition.
 5. Alubricant composition, as defined in claim 1, wherein said compositioncomprises an oil of lubricating viscosity in the range from about 45 SSUat 100*F. to about 6000 SSU at 100*F.
 6. A lubricant composition, asdefined in claim 1, wherein said composition comprises an oil oflubricating viscosity in the range from about 50 SSU at 210*F. to about250 SSU at 210*F.
 7. A lubricant composition, as defined in claim 1,wherein said composition comprises a grease.
 8. A lubricant composition,as defined in claim 1, wherein the sulfur in said mixture is present inan amount from about 0.01 to about 15%, by weight, of the total weightof the mixture.
 9. A lubricant composition, as defined in claim 1,wherein the sulfur in said mixture is present in an amount from about0.5 to about 5%, by weight, of the total weight of the mixture.
 10. Alubricant composition, as defined in claim 1, wherein said mixture ispresent in an amount from about 0.1 to about 30%, by weight, of thetotal weight of the composition.
 11. A lubricant composition, as definedin claim 1, wherein said mixture is present in an amount from about 3 toabout 10%, by weight, of the total weight of the composition.
 12. Amixture of an alkylene oxide polymer and sulfur.
 13. A mixture, asdefined in claim 12, wherein said alkylene oxide polymer comprises thereaction product of about 1 to about 30 moles of an alkylene oxide andabout 70 to 99 moles of a member of the group consisting of alkanols,fatty acids, and alkylphenols.
 14. A mixture, as defined in claim 12,wherein the sulfur is present in an amount from about 0.01 to about 15%,by weight, of the total weight of the mixture.
 15. A mixture, as definedin claim 12, wherein the sulfur is present in an amount from about 0.5to about 5%, by weight, of the mixture.